This invention generally relates to foldable constructions for agricultural implements and deals more particularly with a construction of the type wherein a pair of outrigger implement sections are hingedly connected on respective opposite sides of the center implement section for horizontal swinging movement from a transversely extending ground working position, to a longitudinally extending transport position.
Multiple section, ground conditioning farm implements capable of traversing wide stretches of ground with each sweep but being foldable to permit transport thereof from place to place, have now been in widespread use for several years, and the continuing trend toward large scale farming operations dictates the need for important advancements in foldable construction designs. Several fundamental approaches have been devised in the past to reduce the overall width of wide implement constructions for transport purposes; a number of previous construction designs include a main center section and a transversely extending outrigger section connected to the center section on each side of the latter, the outrigger sections being pivotable either vertically about a longitudinally extending axis at their inner extremity to an essentially longitudinally upright position, or horizontally forwardly or rearwardly to a longitudinally extending position. Although vertically pivotable constructions are attractive due to their simplicity of structure and operation, this design is not practical in connection with especially massive tool sections or dispensing type implements such as grain drills or the like. On the other hand, the horizontal folding approach creates several problems which must be dealt with from a design standpoint. For example, in order to swing the outrigger sections horizontally to their transport position, the ground penetrating tools carried thereby must first be elevated out of engagement with the ground; in the case of relatively lightweight implement sections, the tool carrying frame may be rotated about a transverse axis to pivot the tools out of engagement with the ground as suggested by the implement construction shown in U.S. Pat. No. 3,698,488 to Yoder, et al, however where heavier implement sections are employed, vertically shiftable, hydraulic cylinder operated wheels mounted on the outrigger sections are required to elevate the latter as disclosed in U.S. Pat. No. 3,523,699 to Sinkule, et al. In any event, prior art constructions having relatively heavy outrigger sections require ground-engaging support wheels connected to the outrigger sections which roll along the ground and carry a substantial portion of the weight of each section, when the latter are shifted between their working and transport positions, and when operating in rough or uneven terrain, it is sometimes difficult to bring the outrigger sections into proper registration with the center frame in order to secure the outrigger sections for transport. Furthermore, difficulty is also often encountered in applying sufficient force to produce smooth swinging movement of the outrigger sections over rough terrain, even with the aid of power means.
According to the present invention, a horizontally foldable implement includes a pair of transversely extending outrigger implement tool sections connected to a drawn center frame by a ball and socket-type hinge that provides a weight bearing, radial pivot for both permitting the outrigger sections to cant, rise and fall in accordance with the terrain as well as to permit the outrigger sections to swing horizontally forward to a longitudinally extending transport position. Structure and mechanism is provided to limit the degree of radial pivotal freedom of the outrigger sections and to selectively restrain the latter from vertical pivotal movement about a longitudinally extending axis whereby to cantilever support the latter on the center section when the center frame is raised by means of vertically shiftable wheel means mounted on the center frame. Each of the implement tool sections is provided with a removably mounted, vertically shiftable tool carrying frame structure, and further includes mechanism to allow selective elevational adjustment of the frame structure whereby to allow changes to be made in the depth of ground penetration by the implement tools.
An important object of invention is to provide a multi-section, folding implement construction having outrigger sections connected to an elevatable center frame by hinge means which provide a weight bearing, radial pivotal mounting of the outrigger sections when the latter are disposed in a lowered, ground conditioning position and for supporting the outrigger sections in a cantilever manner whereby the latter are raised out of contact with the ground when the center frame is elevated, and further permitting horizontal swinging movement of the outrigger sections to allow folding of the latter for transport.
As a corollary to the foregoing object it is a further object of the invention to provide a radial pivotal mounting of the mentioned type employing a ball and socket assembly.
Another object of the invention is to provide a novel implement construction having a main tool carrying frame pivotally connected to a draft frame and provided with pivotally mounted wheel means shiftable into and out of engagement with the ground, for raising and lowering the center frame while maintaining the latter in an essentially horizontal position.
A further object of the invention is to provide novel mechanism and structure for selectively changing the depth of penetration of ground working implement tools mounted on an implement tool carrying section, without the need for vertically shiftable wheel means for changing the elevation of the entire tool carrying section.
A still further object of the invention is to provide an implement tool supporting section with a removably mounted tool carrying frame to allow simple interchange of different types of ground conditioning implement tools.
Other and further objects of the invention will be made clear or become apparent in the course of the following description.